This invention relates to a plate-shaped fastener used to mount various instruments and members to interior walls and ceilings of plasterboard by means of screws.
This invention also relates to a driving jig used to obliquely drive the plate-shaped fastener to mount a member or an instrument to a plasterboard wall or a ceiling surface.
A conventional means for mounting various instruments and members to a wall or a ceiling constructed so as not to be accessible to its back, as shown in FIG. 8, includes a plug 4 having a plurality of bendable legs 2 integrally formed at the tip of a flanged sleeve 1, and provided with a nut member 3 at the tip of the group of bendable legs 2. In use, a hole 5 is drilled in a ceiling or wall A, the plug 4 is inserted into the hole 5, a screw inserted into the flanged sleeve 1 is threaded into the nut member 3 and tightened, the nut member 3 is pulled to bend the group of bendable legs 2 so that the plug 4 may not come off, the screw is pulled out, an instrument or member B is superposed on the ceiling or wall A, and a screw 6 is threaded through the instrument or member B into the nut member 3 to fasten the instrument or member B to the ceiling or wall A.
By the way, since such a plug 4 is prevented from coming off by bending the group of bendable legs 2 in the back of the ceiling or wall A, if the screw 6 is tightened strongly, co-turning tends to occur, so that no firm tightening force is obtainable, and also loosening tends to occur due to vibration. The resistance to pulling force is also weak. Moreover, since the plug is complicated in structure, the cost is high.
An object of this invention is to provide a plate-shaped fastener which is less likely to loosen by vibration, which provides tightening high in resistance to pulling force, and which is inexpensive in cost.
Another object of this invention is to provide a driving jig which makes it possible to drive in the plate-shaped fastener accurately at a predetermined angle, and with which the plate-shaped fastener can be held so as not to come off during driving, whereby the plate-shaped fastener can be driven in easily and moreover, the screw position can be clearly indicated when fastening by a screw.